Chacko John, 50, and his 26-year old son Syanu Chacko were detained as the killing of Kevin P Joseph rocked the state with a hartal hitting normal life in Kottayam and the Congress targeting Chief Minister Pinarayi Vijayan for alleged lapse by police in the handling of a complaint by the victim's fiancee.
The two, who had gone underground after the incident, surrendered at a police station in northern Kannur district and were taken into custody, police said adding they were among 14 accused in the case.
Joseph, a Dalit Christian, was abducted on Sunday and killed by a gang of criminals allegedly engaged by his fiancee's family. His body was found in a river in Kollam district on Monday.
His relatives have alleged he was tortured and killed by the gang two days after Joseph and the woman filed a joint application for marriage registration at a sub-registrar office near Kottayam.
Three persons allegedly involved in the crime were taken into custody hours after the recovery of the body while a search was on for nine others.
Earlier on Tuesday, the father and son moved an anticipatory bail plea in the Kerala high court claiming that they had not committed any offence.
In their plea, likely to come up for hearing on Wednesday, the two said they were willing to cooperate in the investigation.
Ernakulam Range IG Vijay Sakhare said the woman's father had a role in the crime.
The body of Joseph was buried in the cemetery of Good Shepherd Church in Kottayam this afternoon in the presence of a large number of locals.
Earlier, the body was brought to his native Kumaranellore village amid poignant scenes. After locals paid their homage, it was taken for burial.
Meanwhile, normal life was affected in Kottayam district by the dawn-to-dusk hartal called by various political parties, including the Congress and Bharatiya Janata Party, and Dalit organisations to protest the killing.
Former chief minister and Congress working committee member A K Antony said Chief Minister Pinarayi Vijayan should take responsibility for the alleged lapse on the part of police in dealing with the case.
Leader of the opposition in the state assembly Ramesh Chennithala demanded resignation of Vijayan.
Jopseph's fiancee, whose father is a Christian and mother a Muslim, alleged laxity on the part of police when she approached the Gandhinagar police station near Kottayam with a missing complaint earlier.
The police did not move even after she appealed to the Sub Inspector that Joseph's life was in danger and he should be rescued, she told reporters in Kottayam.
Bursting into tears, the woman said she was 'Kevin's wife and will stay at his residence'.
Kerala Human Rights Commission has said it was suspected to be a case of honour killing and ordered the state police chief to submit a report in three weeks.
Sub-Inspector M S Shibu and Grade ASI Sunnymon of the Gandhinagar police station were yesterday suspended for laxity while Kottayam District Superintendent of Police V M Mohammed Rafique transferred following the incident.
The chief minister has described the incident as 'unfortunate' and said it should not have happened.
Antony said there was a grave lapse on the part of the police in dealing with the case and it cannot be justified.
"The government and chief minister have to take the responsibility for this," he said.
Noting that a girl was killed in a similar 'honour killing' by her father a month ago in Malappuram, he said it was not proper for the Kerala society to remain silent over such incidents.
These honour killings actually point to the degradation of cultural and social values, he said in New Delhi.
"Casteism and primitive rituals which the state had driven away through social reforms have started to come back...Kerala is virtually turning as lunatic asylum as described by Swami Vivekananda," he said.
The general public, political leadership and social outfits also should perform their responsibilities, he added.
Chennithala demanded the resignation of Vijayan, claiming that the state police force under him had crumbled.
Suspension of a few police personnel in connection with the incident was an eye wash, he charged.
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